Re: [PATCH v11 02/17] Add a new struct for device to manipulate external buffer.

[Ben Hutchings <bhutchings@solarflare.com>]

On Sat, 2010-09-25 at 12:27 +0800, xiaohui.xin@intel.com wrote:
> From: Xin Xiaohui <xiaohui.xin@intel.com>
> 
> Signed-off-by: Xin Xiaohui <xiaohui.xin@intel.com>
> Signed-off-by: Zhao Yu <yzhao81new@gmail.com>
> Reviewed-by: Jeff Dike <jdike@linux.intel.com>
> ---
>  include/linux/netdevice.h |   22 +++++++++++++++++++++-
>  1 files changed, 21 insertions(+), 1 deletions(-)
> 
> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
> index fa8b476..ba582e1 100644
> --- a/include/linux/netdevice.h
> +++ b/include/linux/netdevice.h
> @@ -530,6 +530,25 @@ struct netdev_queue {
>  	unsigned long		tx_dropped;
>  } ____cacheline_aligned_in_smp;
>  
> +/* Add a structure in structure net_device, the new field is
> + * named as mp_port. It's for mediate passthru (zero-copy).

That belongs in the commit message.

> + * It contains the capability for the net device driver,
> + * a socket, and an external buffer creator, external means
> + * skb buffer belongs to the device may not be allocated from
> + * kernel space.

Who sets which fields in this structure?  Can you make this a kernel-doc
comment specifying the use of each field?

Ben.

> + */
> +struct mpassthru_port	{
> +	int		hdr_len;
> +	int		data_len;
> +	int		npages;
> +	unsigned	flags;
> +	struct socket	*sock;
> +	int		vnet_hlen;
> +	struct skb_ext_page *(*ctor)(struct mpassthru_port *,
> +				struct sk_buff *, int);
> +	struct skb_ext_page *(*hash)(struct net_device *,
> +				struct page *);
> +};
>  
>  /*
>   * This structure defines the management hooks for network devices.
> @@ -952,7 +971,8 @@ struct net_device {
>  	struct macvlan_port	*macvlan_port;
>  	/* GARP */
>  	struct garp_port	*garp_port;
> -
> +	/* mpassthru */
> +	struct mpassthru_port	*mp_port;
>  	/* class/net/name entry */
>  	struct device		dev;
>  	/* space for optional device, statistics, and wireless sysfs groups */

-- 
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.